1. Field of the Invention
The present invention relates to the field of image display devices and electrochromic modules thereof, and more particularly to a 3D image display device and an electrochromic module thereof capable of changing direction and displaying 3D images.
2. Description of the Related Art
At present, 3D images are mainly divided into two types, respectively: 3D images viewed by naked eyes and viewed by wearing shutter glasses.
With reference to FIGS. 1 and 2 for schematic views of a 3D image display device that generates 3D images by shutter glasses in accordance with a prior art and its synchronous control process respectively, after a light produced by a backlight device 13 is passed through an LCD panel 12 in the conventional 3D image display device 1, a viewer's left and right eyes see left-eye image information and right-eye image information at different time points respectively to produce a visual separation effect, and the alternately displayed left and right-eye image information are operated synchronously by shutter glasses 11 and a control circuit (not shown in the figure), wherein a switch signal is provided for controlling the ON and OFF of the left and right eyes of the shutter glasses 11. After the switch process and the receipt of images by the LCD panel 12 are synchronized to display the left-eye image information, the shutter will block the vision of the right eye. On the other hand, when the right-eye image information is displayed, the shutter will block the vision of the left eye. Therefore, the left-eye and right-eye images are displayed alternately, and a 3D visual effect can be produced by the visual retention effect. This method of forming 3D images is called “Time Division”.
In addition, there is a method called Wavelength Division, wherein red or green colored glasses is worn to view left-eye and right-eye images, and the viewer's left eye can see a red vision image only and the viewer's right eye can see green vision image, and the left and right images of different colors are processed to form a 3D image.
In addition, there is a 3D image display device manufacturing based on the Pulfrich effect, and the 3D image display device comprises a pair of Pulfrich 3D glasses, and one lens of the 3D glasses further comprises a neutral filter, such that the different transmittance of the left and right lenses can produce a visual illusion, since the viewer's brain senses the stimulation of a dark object slightly slower that the stimulation of a bright object. Although both eyes can see the same image, the speed of transmitting images to the viewer's brain is slower through the filter, so that a virtual spatial depth is created to produce a 3D effect.
In the aforementioned method of viewing 3D images by wearing the glasses, the related technology is matured and used extensively in movie, television and projector industries. However, since the technology requires wearing glasses additional, it causes tremendous inconvenience for viewers already wearing a pair of near-sighted or far-sighted glasses to wear another pair of glasses to view the 3D images. If the 3D glasses are worn in public, three will be a sanitary issue. Furthermore, many viewers may become dizzy and have nausea by wearing glasses of this sort, and thus incurring physiological burdens to wearers, and limiting the application of such 3D image technology.
The naked-eye 3D image display technology is mainly divided into two types: lenticular and barrier, wherein the lenticular includes a plurality of slender rectangular convex lenses arranged along an axis, and the principle of optical refraction is used for generating different left-eye and right-eye images. Compared with the barrier, the lenticular uses the light refraction to achieve the light division effect, so that there is less light loss, and a better brightness, but the refraction effect at the edge of the lenses is very limited, and the refraction effect is very poor. Since it is difficult to control the precision of manufacturing the lenticular lenses, stray lights will be produced easily to affect the overall display effect adversely.
Furthermore, the barrier uses the whole row of barriers to limit the exit light to a specific angle, and only images from a certain angle can be transmitted to the viewer's left and right eyes only to generate the 3D image. Compared with the lenticular lenses, the single-eye image is clearer. However, the overall brightness and resolution of the image will be reduced due to the feature of the structure.
As material technologies advance, electrochromic materials have the coloration or decoloration effect and they are gradually used as the parallax barrier required for displaying naked-eye 3D images. As disclosed in R.O.C.(TW) Pat. No. M368088 entitled “Integrated electrochromic 2D/3D display device, R.O.C.(TW) Pat. No. M371902 entitled “Display device for switching 2D image/3D image display screen”, and U.S. Pat. Application No. 2006087499 entitled “Autostereoscopic 3D display device and fabrication method thereof”, electrochromic materials are used as a parallax barrier device for displaying 3D images. However, the aforementioned devices have the drawbacks of lacking the necessary electrolyte layer and the required ions supplied to the electrochromic layer, so that the electrochromic element cannot produce a reversible oxidation or reduction to complete the coloration or decoloration. Therefore, the foregoing patents are not feasible in practical applications. In addition, the transparent electrode layer and electrochromic material layer of the parallax barrier device are grid patterned, and whose manufacturing process requires a precise alignment for coating, spluttering or etching each laminated layer, and thus the manufacturing process is very complicated, and the resistance value is increased to retard the response time, and all laminated layers are grid patterned, so that a hollow area is formed between one grid and the other, and the overall penetration, refraction and reflection of the light will be affected adversely. Even for the general 2D display, the video display quality of the display device will be affected to cause problems related to color difference and uneven brightness.
Furthermore, the prior art used for displaying 3D images can display the 3D images in one direction only. As to the portable electronic products such as mobile phones, PDAs, and GPSs, users can only turn them to a specific direction before viewing the 3D images, but they cannot change the angle of displaying the 3D images flexibly. Obviously, the application according to the prior art is very inconvenient.